Turkey Tuesday condemned the UN's signing "an action plan" with the PKK terror group.
"Turkey strongly condemns the UN's signing an 'action plan' with the PKK/YPG terrorists without the knowledge of its members," the Foreign Ministry said in a statement.
The UN signed a controversial deal with the SDF, which is controlled by the YPG/PKK terror group in Syria, to end the recruitment of children for terrorist actions.
Virginia Gamba, the UN Secretary General's special representative on children in armed conflicts, met with YPG commander Mazloum Abdi and signed an agreement over the weekend in Geneva.
"It cannot be explained in any way that the UN signed an agreement with the PKK terror group. This is also an obvious violation of the UN's decisions on terrorism by itself," the statement added.
Turkey also underlined that it is "unacceptable" that UN signed a deal with the PKK to solve the problem, although it affirms that the terror group commits crimes against humanity and international law, including forceful recruitment of children.
The so-called agreement aims to end SDF's use and recruitment of individuals under the age of 18.
The YPG is the Syrian branch of the PKK, and works under the label of the SDF. It is a designated terror group in Turkey, the EU and the U.S.
The activities of the YPG/PKK terrorist group have been a major security concern for Ankara, while the U.S. viewed the group as a "reliable partner" in the fight against Daesh.
The PKK has waged a terror campaign against Turkey for more than 30 years and been responsible for the deaths of nearly 40,000 people, including women and children.